Are People Getting Smarter or Dumber?

Article excerpt

IN MY DARK MOMENTS (usually after grading a physics exam), I sometimes wonder if there has been a general deterioration in human reasoning ability. Fortunately, on most days this feeling is fleeting. On other occasions when I am pleasantly surprised by a particularly insightful student comment I ask myself the reverse question: might people actually be getting smatter? I'm unaware of any polls on either the smarter or dumber question, but I imagine that when young and old people look at one another across the generational divide, each might often tend to regard its group with greater favor in terms of intelligence.

Anyone looking for evidence that people are getting dumber can find many examples of stupidity that seem to be on the rise in today's world. One of my candidates would be the increasing number of people who choose to play the lottery, but only when the jackpot reaches $20 million, believing that anything less won't make a major change in their lives. (1) One compilation of stupidity by individuals that makes for quite interesting reading is the (sometimes apocryphal) Darwin Awards, which are simultaneously sad, cruel, and funny, commemorating those who have improved the human gene pool by removing themselves from it. (2)

Contrary to popular belief, however, Darwinian evolution says nothing about whether intelligence should increase or decrease over time. There is little doubt about the actual increase that has occurred when we compare the relative intelligence of humans with that of the extinct species from which we have descended. But, development toward increased intelligence shows only that in the environments these species found themselves, greater intelligence had survival value. It is quite possible to imagine a different planetary history and different environments, in which intelligence would not have had great value. (One can easily imagine post-apocalyptic futures in which keen senses, brute strength, ruthlessness, and ability to with-stand hardship or extreme heat would have much greater survival value than intelligence.)

Any serious attempt to try to learn whether people are getting smarter or dumber over time immediately runs into at least four difficult questions:

   What do we mean by intelligence?
   How can intelligence be measured?
   Which people are we talking about?
   What time interval are we considering?

Sometimes half-jokingly it is said that intelligence is what intelligence tests test. While that circular definition is not particularly helpful in clarifying the meaning of intelligence, it is not entirely useless either, if the ability to score high on intelligence tests correlates highly with real world abilities that are normally thought of as representing examples of mental ability, the tests do acquire a degree of credibility. After all, a similarly circular definition of time as: "that which a clock measures" was instrumental in leading Albert Einstein to his theory of Relativity.

Nowadays, it has become fashionable to note that there are many kinds of intelligence, and that abstract reasoning ability no longer should be regarded as the sole or even the primary measure. According to Howard Gardner's theory of multiple intelligences there are seven types of intelligence: verbal/linguistic, musical, logical/mathematical, spatial, body-kinesthetic, intrapersonal (e.g., insight, metacognition) and interpersonal (e.g., social skills). (3) Only two of these seven forts (verbal/linguistic and logical/mathematical) are tested on conventional IQ tests. Given Gardner's theory of multiple intelligences, one might regard a possible loss of reasoning ability and a corresponding gain of "emotional intelligence" as simply a shift from one kind of intelligence to another, rather than a dumbing down of society. Notwithstanding Gardner's multiple intelligence theory, however, when we address the question of whether people are getting smatter or dumber over time, the primary focus will be on verbal/linguistic and logical/mathematical intelligence, which are measured by IQ tests. …